software backlash compensation dude

[lamartinada]

Hi, I'm intereseted in purchase an Acorn cnc board for my Sieg X2 mill. I have read that this software supports backlash compensation and I ask me the follow:

When I do the retrofit, if I don't change the trapezial screw (default comes with machine) by ballscrews, there is some lash in three axis. Can the software compensate this backlash and cut round circles only with this feature or there are some limitation lash distance??

I hope you can help me to solve this question. Thanks!!

[mfry]

The software will let you set any values. But realistically, if it's compensating more than .001" to. 002" you will see it in your circles. On any machine, any control system. With stepper motors and acme screws it's just impossible to do some things.

[diycncscott]

As mfry pointed out, the the Acorn does have backlash compensation. That said, your accuracy can only be as good as the mechanical accuracy of the machine. Especially on an open loop system.

When you have mechanical play on the machine, cutting forces can push the table anywhere in that deadband. So yes, the control can add backlash compensation to an axis when it turns around and it does help quite a bit, especially on point to point moves, but at quadrants in arcs and other places where cutting forces are pushing or pulling the table into the lash dead band it can't do anything. You can end up with flats at the quadrants at what appear to be egg shaped circles which are really are just a reflection of the differences between the amount of lash in the X and Y and resulting flats